Function Points

Test Your Knowledge

Function Points Quiz

Instructions: Choose the best answer for each question.

1. What is the primary advantage of using Function Points over Lines of Code (LOC) for software sizing?

a) Function Points are easier to calculate. b) Function Points consider only the physical code size. c) Function Points measure the functional complexity of the system. d) Function Points are more suitable for small-scale projects.

2. Which of the following is NOT a component of Function Point analysis?

a) External Inputs (EI) b) External Outputs (EO) c) Internal Data Structures (IDS) d) External Interface Files (EIF)

3. What is the main purpose of determining the complexity of each Function Point component?

a) To simplify the calculation process. b) To identify potential design flaws. c) To accurately reflect the effort required for implementation. d) To compare the size of different software systems.

4. Which of the following is NOT a benefit of using Function Points for software estimation?

a) Improved communication between stakeholders. b) Accurate cost estimation and resource allocation. c) Easier project management for waterfall methodologies. d) Objective comparison of software project sizes.

5. What is the final step in the Function Point analysis process?

a) Identifying functional components. b) Classifying components based on their type. c) Determining complexity of each component. d) Calculating the total Function Points using predefined formulas.

Function Points Exercise

Scenario:

You are tasked with estimating the size of a new online banking application using Function Points. The application has the following features:

• Customer login: Users can log in with their username and password.
• Account balance inquiry: Users can view their account balances.
• Transaction history: Users can view a detailed history of their transactions.
• Transfer funds: Users can transfer funds between their own accounts.
• Bill payment: Users can pay bills directly from their accounts.

Instructions:

1. Identify the functional components of the application and categorize them based on the five Function Point elements (EI, EO, EQ, ILF, EIF).
2. Determine a complexity rating for each component (simple, average, complex).
3. Calculate the total Function Points based on the complexity and component count.

Techniques

Chapter 1: Techniques

Function Point Analysis: A Detailed Look at the Techniques

Function Point analysis involves a structured approach to measuring software functionality. This chapter delves deeper into the specific techniques used to calculate Function Points.

1.1 Counting Techniques:

• Unweighted Function Points (UFP): This technique focuses on simply counting the number of functional components without considering their complexity. Each instance of EI, EO, EQ, ILF, and EIF is given a weight of 1.
• Weighted Function Points (WFP): This technique accounts for the complexity of each component by assigning weights based on specific factors. The complexity levels are often categorized as low, average, and high, with corresponding weights.

1.2 Function Point Value (FPV):

• FPV = Count x Complexity Weight
• This formula is applied to each component type, resulting in a weighted count for each EI, EO, EQ, ILF, and EIF.
• The total FPV is the sum of the individual component FPVs.

1.3 Value Adjustment Factor (VAF):

• The VAF accounts for factors like data communication, distributed processing, performance, and security.
• These factors are assigned a rating based on their impact on the overall system complexity.
• The VAF is a multiplier that adjusts the total FPV to account for the added complexity.

1.4 Calculation Formula:

• Function Points (FP) = (FPV x VAF) / 100
• This formula provides the final Function Point value, which represents the software's functional size and complexity.

1.5 Different Function Point Counting Standards:

• IFPUG (International Function Point Users Group): This is the most widely recognized standard for Function Point counting.
• COSMIC (Counting and Sizing Method for Information Systems): Another popular standard, often used in Europe.
• NESMA (National Estimating Standards for Software Maintenance and Applications): Focuses on maintenance and application sizing.

1.6 Advantages of Different Techniques:

• UFP: Simple and quick for initial estimates, but less accurate for complex systems.
• WFP: Provides a more refined estimate by considering complexity, but requires more detailed analysis.
• VAF: Accounts for external factors that impact complexity, leading to a more accurate representation.

1.7 Conclusion:

By understanding these techniques, software teams can choose the most appropriate method for their specific needs, ensuring accurate and reliable function point calculations. This information forms the foundation for accurate software sizing and estimation, leading to better project management and decision-making.